Last year the Select Committee for Political and Constitutional Reform published a bulky report with a question as its title: A New Magna Carta? The Committee’s Chairman Graham Allen MP launched it in July at the British Library. It set out three options for the overall reform of the UK’s constitution: a codification of what exists; a consolidation of existing laws and conventions into a unified framework; a written constitution. It issued a call for public responses. To encourage the imagination and inspire people the Committee also lay down a challenge: come up with your own preamble to the Constitution of the future. The air is full of talk about the constitution, about Magna Carta, about the need to renew democracy. So this is …